Wireless patient monitoring system

ABSTRACT

A device for obtaining physiological information of a medical patient and wirelessly transmitting the obtained physiological information to a wireless receiver.

BACKGROUND

Hospitals, nursing homes, and other patient care facilities typically include patient monitoring devices at one or more bedsides in the facility. Patient monitoring devices generally include sensors, processing equipment, and displays for obtaining and analyzing a medical patient's physiological parameters such as blood oxygen saturation level, respiratory rate, and the like. Clinicians, including doctors, nurses, and other medical personnel, use the physiological parameters obtained from patient monitors to diagnose illnesses and to prescribe treatments. Clinicians also use the physiological parameters to monitor patients during various clinical situations to determine whether to increase the level of medical care given to patients.

Blood pressure is one example of a physiological parameter that can be monitored. Many devices allow blood pressure to be measured by sphygmomanometer systems that utilize an inflatable cuff applied to a person's arm. The cuff is inflated to a pressure level high enough to occlude a major artery. When air is slowly released from the cuff, blood pressure can be estimated by detecting “Korotkoff” sounds using a stethoscope or other detection means placed over the artery.

SUMMARY

In certain embodiments, a device for obtaining physiological information of a medical patient can include a blood pressure device that can be coupled to a medical patient and a wireless transceiver electrically coupled with the blood pressure device. The wireless transceiver can wirelessly transmit blood pressure data received by the blood pressure device and physiological data received from one or more physiological sensors coupled to the blood pressure device. To further increase patient mobility, in some embodiments, a single cable is also provided for connecting multiple different types of sensors together.

For purposes of summarizing the disclosure, certain aspects, advantages and novel features of the inventions have been described herein. It is to be understood that not necessarily all such advantages can be achieved in accordance with any particular embodiment of the inventions disclosed herein. Thus, the inventions disclosed herein can be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as can be taught or suggested herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments will be described hereinafter with reference to the accompanying drawings. These embodiments are illustrated and described by example only, and are not intended to limit the scope of the disclosure. In the drawings, similar elements have similar reference numerals.

FIGS. 1A and 1B illustrate embodiments of wireless patient monitoring systems;

FIGS. 2A and 2B illustrate embodiments of wireless patient monitoring systems having a single cable connection system;

FIGS. 3A and 3B illustrates additional embodiment of patient monitoring systems;

FIGS. 4A and 4B illustrate embodiments of an optical ear sensor and an acoustic sensor connected via a single cable connection system;

FIG. 5 illustrates an embodiment of a wireless transceiver that can be used with any of the patient monitoring systems described above;

FIGS. 6A through 6C illustrate additional embodiments of patient monitoring systems; and

FIG. 7 illustrates an embodiment of a physiological parameter display that can be used with any of the patient monitoring systems described above.

FIG. 8 illustrates a further embodiment of a patient monitoring system.

DETAILED DESCRIPTION

In clinical settings, medical sensors are often attached to patients to monitor physiological parameters of the patients. Some examples of medical sensors include blood oxygen sensors, blood pressure sensors, and acoustic respiratory sensors. Typically, each sensor attached to a patient is connected to a bedside monitoring device with a cable. The more cables that couple the patient to the bedside monitoring device, the more the patient's freedom of movement can be restricted. In addition, cables pose a tripping hazard to health care workers and make it difficult to perform rapid transport to therapeutic areas such as the operating room when emergency situations arise.

This disclosure describes embodiments of wireless patient monitoring systems that include a wireless device coupled to a patient and to one or more sensors. In one embodiment, the wireless device transmits sensor data obtained from the sensors to a patient monitor. By transmitting the sensor data wirelessly, these patient monitoring systems can advantageously replace some or all cables that connect patients to bedside monitoring devices. To further increase patient mobility and comfort, in some embodiments, a single cable connection system is also provided for connecting multiple different types of sensors together.

These patient monitoring systems are primarily described in the context of an example blood pressure cuff that includes a wireless transceiver. The blood pressure cuff and/or wireless transceiver can also be coupled to additional sensors, such as optical sensors, acoustic sensors, and/or electrocardiograph sensors. The wireless transceiver can transmit blood pressure data and sensor data from the other sensors to a wireless receiver, which can be a patient monitor. These and other features described herein can be applied to a variety of sensor configurations, including configurations that do not include a blood pressure cuff.

FIGS. 1A and 1B illustrate embodiments of wireless patient monitoring systems 100A, 100B, respectively. In the wireless patient monitoring systems 100 shown, a blood pressure device 110 is connected to a patient 101. The blood pressure device 110 includes a wireless transceiver 116, which can transmit sensor data obtained from the patient 101 to a wireless transreceiver 120. Thus, the patient 101 is advantageously not physically coupled to a bedside monitor in the depicted embodiment and can therefore have greater freedom of movement.

Referring to FIG. 1A, the blood pressure device 110 a includes an inflatable cuff 112, which can be an oscillometric cuff that is actuated electronically (e.g., via intelligent cuff inflation and/or based on a time interval) to obtain blood pressure information. The cuff 112 is coupled to a wireless transceiver 116. The blood pressure device 110 a is also coupled to a fingertip optical sensor 102 via a cable 107. The optical sensor 102 can include one or more emitters and detectors for obtaining physiological information indicative of one or more blood parameters of the patient 101. These parameters can include various blood analytes such as oxygen, carbon monoxide, methemoglobin, total hemoglobin, glucose, proteins, glucose, lipids, a percentage thereof (e.g., concentration or saturation), and the like. The optical sensor 102 can also be used to obtain a photoplethysmograph, a measure of plethysmograph variability, a measure of blood perfusion, and the like.

Additionally, the blood pressure device 110 a is coupled to an acoustic sensor 104 a via a cable 105. The cable 105 connecting the acoustic sensor 104 a to the blood pressure device 110 includes two portions, namely a cable 105 a and a cable 105 b. The cable 105 a connects the acoustic sensor 104 a to an anchor 104 b, which is coupled to the blood pressure device 110 a via the cable 105 b. The anchor 104 b can be adhered to the patient's skin to reduce noise due to accidental tugging of the acoustic sensor 104 a.

The acoustic sensor 104 a can be a piezoelectric sensor or the like that obtains physiological information reflective of one or more respiratory parameters of the patient 101. These parameters can include, for example, respiratory rate, inspiratory time, expiratory time, inspiration-to-expiration ratio, inspiratory flow, expiratory flow, tidal volume, minute volume, apnea duration, breath sounds, rales, rhonchi, stridor, and changes in breath sounds such as decreased volume or change in airflow. In addition, in some cases the respiratory sensor 104 a, or another lead of the respiratory sensor 104 a (not shown), can measure other physiological sounds such as heart rate (e.g., to help with probe-off detection), heart sounds (e.g., S1, S2, S3, S4, and murmurs), and changes in heart sounds such as normal to murmur or split heart sounds indicating fluid overload. In some implementations, a second acoustic respiratory sensor can be provided over the patient's 101 chest for additional heart sound detection. In one embodiment, the acoustic sensor 104 can include any of the features described in U.S. Patent Application No. 61/141,584, filed Dec. 30, 2008, titled “Acoustic Sensor Assembly,” the disclosure of which is hereby incorporated by reference in its entirety.

The acoustic sensor 104 can also be used to generate an exciter waveform that can be detected by the optical sensor 102 at the fingertip, by an optical sensor attached to an ear of the patient (see FIGS. 2A, 3), by an ECG sensor (see FIG. 2C), or by another acoustic sensor (not shown). The velocity of the exciter waveform can be calculated by a processor (such as a processor in the wireless transceiver 120, described below). From this velocity, the processor can derive a blood pressure measurement or blood pressure estimate. The processor can output the blood pressure measurement for display. The processor can also use the blood pressure measurement to determine whether to trigger the blood pressure cuff 112.

In another embodiment, the acoustic sensor 104 placed on the upper chest can be advantageously combined with an ECG electrode (such as in structure 208 of FIG. 2B), thereby providing dual benefit of two signals generated from a single mechanical assembly. The timing relationship from fidicial markers from the ECG signal, related cardiac acoustic signal and the resulting peripheral pulse from the finger pulse oximeters produces a transit time that correlates to the cardiovascular performance such as blood pressure, vascular tone, vascular volume and cardiac mechanical function. Pulse wave transit time or PWTT in currently available systems depends on ECG as the sole reference point, but such systems may not be able to isolate the transit time variables associated to cardiac functions, such as the pre-ejection period (PEP). In certain embodiments, the addition of the cardiac acoustical signal allows isolation of the cardiac functions and provides additional cardiac performance metrics. Timing calculations can be performed by the processor in the wireless transceiver 120 or a in distributed processor found in an on-body structure (e.g., such as any of the devices herein or below: 112, 210, 230, 402, 806).

In certain embodiments, the wireless patient monitoring system 100 uses some or all of the velocity-based blood pressure measurement techniques described in U.S. Pat. No. 5,590,649, filed Apr. 15, 1994, titled “Apparatus and Method for Measuring an Induced Perturbation to Determine Blood Pressure,” or in U.S. Pat. No. 5,785,659, filed Jan. 17, 1996, titled “Automatically Activated Blood Pressure Measurement Device,” the disclosures of which are hereby incorporated by reference in their entirety. An example display related to such blood pressure calculations is described below with respect to FIG. 7.

The wireless transceiver 116 can transmit data using any of a variety of wireless technologies, such as Wi-Fi (802.11x), Bluetooth (802.15.2), Zigbee (802.15.4), cellular telephony, infrared, RFID, satellite transmission, proprietary protocols, combinations of the same, and the like. The wireless transceiver 116 can perform solely telemetry functions, such as measuring and reporting information about the patient 101. Alternatively, the wireless transceiver 116 can be a transceiver that also receives data and/or instructions, as will be described in further detail below.

The wireless receiver 120 receives information from and/or sends information to the wireless transceiver via an antenna (not shown). In certain embodiments, the wireless receiver 120 is a patient monitor. As such, the wireless receiver 120 can include one or more processors that process sensor signals received from the wireless transceiver 116 corresponding to the sensors 102 a, 102 b, 104, and/or 106 in order to derive any of the physiological parameters described above. The wireless transceiver 120 can also display any of these parameters, including trends, waveforms, related alarms, and the like. The wireless receiver 120 can further include a computer-readable storage medium, such as a physical storage device, for storing the physiological data. The wireless transceiver 120 can also include a network interface for communicating the physiological data to one or more hosts over a network, such as to a nurse's station computer in a hospital network.

Moreover, in certain embodiments, the wireless transceiver 116 can send raw data for processing to a central nurse's station computer, to a clinician device, and/or to a bedside device (e.g., the receiver 116). The wireless transceiver 116 can also send raw data to a central nurse's station computer, clinician device, and/or to a bedside device for calculation, which retransmits calculated measurements back to the blood pressure device 110 (or to the bedside device). The wireless transceiver 116 can also calculate measurements from the raw data and send the measurements to a central nurse's station computer, to a pager or other clinician device, or to a bedside device (e.g., the receiver 116). Many other configurations of data transmission are possible.

In addition to deriving any of the parameters mentioned above from the data obtained from the sensors 102 a, 102 b, 104, and/or 106, the wireless transceiver 120 can also determine various measures of data confidence, such as the data confidence indicators described in U.S. Pat. No. 7,024,233 entitled “Pulse oximetry data confidence indicator,” the disclosure of which is hereby incorporated by reference in its entirety. The wireless transceiver 120 can also determine a perfusion index, such as the perfusion index described in U.S. Pat. No. 7,292,883 entitled “Physiological assessment system,” the disclosure of which is hereby incorporated by reference in its entirety. Moreover, the wireless transceiver 120 can determine a plethysmograph variability index (PVI), such as the PVI described in U.S. Publication No. 2008/0188760 entitled “Plethysmograph variability processor,” the disclosure of which is hereby incorporated by reference in its entirety.

In addition, the wireless transceiver 120 can send data and instructions to the wireless transceiver 116 in some embodiments. For instance, the wireless transceiver 120 can intelligently determine when to inflate the cuff 112 and can send inflation signals to the transceiver 116. Similarly, the wireless transceiver 120 can remotely control any other sensors that can be attached to the transceiver 116 or the cuff 112. The transceiver 120 can send software or firmware updates to the transceiver 116. Moreover, the transceiver 120 (or the transceiver 116) can adjust the amount of signal data transmitted by the transceiver 116 based at least in part on the acuity of the patient, using, for example, any of the techniques described in U.S. Patent Publication No. 2009/0119330, filed Jan. 7, 2009, titled “Systems and Methods for Storing, Analyzing, and Retrieving Medical Data,” the disclosure of which is hereby incorporated by reference in its entirety.

In alternative embodiments, the wireless transceiver 116 can perform some or all of the patient monitor functions described above, instead of or in addition to the monitoring functions described above with respect to the wireless transceiver 120. In some cases, the wireless transceiver 116 might also include a display that outputs data reflecting any of the parameters described above (see, e.g., FIG. 5). Thus, the wireless transceiver 116 can either send raw signal data to be processed by the wireless transceiver 120, can send processed signal data to be displayed and/or passed on by the wireless transceiver 120, or can perform some combination of the above. Moreover, in some implementations, the wireless transceiver 116 can perform at least some front-end processing of the data, such as bandpass filtering, analog-to-digital conversion, and/or signal conditioning, prior to sending the data to the transceiver 120. An alternative embodiment may include at least some front end processing embedded in any of the the sensors described herein (such as sensors 102, 104, 204, 202, 208, 412, 804, 840, 808) or cable hub 806 (see FIG. 8).

In certain embodiments, the cuff 112 is a reusable, disposable, or resposable device. Similarly, any of the sensors 102, 104 a or cables 105, 107 can be disposable or resposable. Resposable devices can include devices that are partially disposable and partially reusable. Thus, for example, the acoustic sensor 104 a can include reusable electronics but a disposable contact surface (such as an adhesive) where the sensor 104 a comes into contact with the patient's skin. Generally, any of the sensors, cuffs, and cables described herein can be reusable, disposable, or resposable.

The cuff 112 can also can have its own power (e.g., via batteries) either as extra power or as a sole source of power for the transceiver 116. The batteries can be disposable or reusable. In some embodiments, the cuff 112 can include one or more photovoltaic solar cells or other power sources. Likewise, batteries, solar sources, or other power sources can be provided for either of the sensors 102, 104 a.

Referring to FIG. 1B, another embodiment of the system 100B is shown. In the system 100B, the blood pressure device 110 b can communicate wirelessly with the acoustic sensor 104 a and with the optical sensor 102. For instance, wireless transceivers (not shown) can be provided in one or both of the sensors 102, 104 a, using any of the wireless technologies described above. The wireless transceivers can transmit data, raw signals, processed signals, conditioned signals, or the like to the blood pressure device 110 b. The blood pressure device 110 b can transmit these signals on to the wireless transceiver 120. In addition, in some embodiments, the blood pressure device 110 b can also process the signals received from the sensors 102, 104 a prior to transmitting the signals to the wireless transceiver 120. The sensors 102, 104 a can also transmit data, raw signals, processed signals, conditioned signals, or the like directly to the wireless transceiver 120 or patient monitor. In one embodiment, the system 100B shown can be considered to be a body LAN, piconet, or other individual network.

FIGS. 2A and 2B illustrate additional embodiments of patient monitoring systems 200A and 200B, respectively. In particular, FIG. 2A illustrates a wireless patient monitoring system 200A, while FIG. 2B illustrates a standalone patient monitoring system 200B.

Referring specifically to FIG. 2A, a blood pressure device 210 a is connected to a patient 201. The blood pressure device 210 a includes a wireless transceiver 216 a, which can transmit sensor data obtained from the patient 201 to a wireless receiver at 220 via antenna 218. In the depicted embodiment, the blood pressure device 210 a includes an inflatable cuff 212 a, which can include any of the features of the cuff 112 described above. Additionally, the cuff 212 a includes a pocket 214, which holds the wireless transceiver 216 a (shown by dashed lines). The wireless transceiver 216 a can be electrically connected to the cuff 212 a via a connector (see, e.g., FIG. 5) in some embodiments. As will be described elsewhere herein, the form of attachment of the wireless transceiver 216 a to the cuff 212 a is not restricted to a pocket connection mechanism and can vary in other implementations.

The wireless transceiver 216 a is also coupled to various sensors in FIG. 2A, including an acoustic sensor 204 a and an optical ear sensor 202 a. The acoustic sensor 204 a can have any of the features of the acoustic sensor 104 described above. The ear clip sensor 202 a can be an optical sensor that obtains physiological information regarding one or more blood parameters of the patient 201. These parameters can include any of the blood-related parameters described above with respect to the optical sensor 102. In one embodiment, the ear clip sensor 202 a is an LNOP TC-I ear reusable sensor available from Masimo® Corporation of Irvine, Calif. In other embodiments, the ear clip sensor 202 a is a concha ear sensor (see FIGS. 4A and 4B).

Advantageously, in the depicted embodiment, the sensors 202 a, 204 a are coupled to the wireless transceiver 216 a via a single cable 205. The cable 205 is shown having two sections, a cable 205 a and a cable 205 b. For example, the wireless transceiver 216 a is coupled to an acoustic sensor 204 a via the cable 205 b. In turn, the acoustic sensor 204 a is coupled to the optical ear sensor 202 a via the cable 205 a. Advantageously, because the sensors 202 a, 204 are attached to the wireless transceiver 216 in the cuff 212 in the depicted embodiment, the cable 205 is relatively short and can thereby increase the patient's 201 freedom of movement. Moreover, because a single cable 205 is used to connect both sensors 202 a, 204 a, the patient's mobility and comfort can be further enhanced.

In some embodiments, the cable 205 is a shared cable 205 that is shared by the optical ear sensor 202 a and the acoustic sensor 204 a. The shared cable 205 can share power and ground lines for each of the sensors 202 a, 204 a. Signal lines in the cable 205 can convey signals from the sensors 202 a, 204 a to the wireless transceiver 216 and/or instructions from the wireless transceiver 216 to the sensors 202 a, 204 a. The signal lines can be separate within the cable 205 for the different sensors 202 a, 204 a. Alternatively, the signal lines can be shared as well, forming an electrical bus.

The two cables 205 a, 205 a can be part of a single cable or can be separate cables 205 a, 205 b. As a single cable 205, in one embodiment, the cable 205 a, 205 b can connect to the acoustic sensor 204 a via a single connector. As separate cables, in one embodiment, the cable 205 b can be connected to a first port on the acoustic sensor 204 a and the cable 205 a can be coupled to a second port on the acoustic sensor 204 a.

FIG. 2B further illustrates an embodiment of the cable 205 in the context of a standalone patient monitoring system 200B. In the standalone patient monitoring system 200B, a blood pressure device 210 b is provided that includes a patient monitor 216 b disposed on a cuff 212 b. The patient monitor 216 b includes a display 219 for outputting physiological parameter measurements, trends, waveforms, patient data, and optionally other data for presentation to a clinician. The display 219 can be an LCD display, for example, with a touch screen or the like. The patient monitor 216 b can act as a standalone device, not needing to communicate with other devices to process and measure physiological parameters. In some embodiments, the patient monitor 216 b can also include any of the wireless functionality described above.

The patient monitor 216 b can be integrated into the cuff 212 b or can be detachable from the cuff 212 b. In one embodiment, the patient monitor 216 b can be a readily available mobile computing device with a patient monitoring software application. For example, the patient monitor 216 b can be a smart phone, personal digital assistant (PDA), or other wireless device. The patient monitoring software application on the device can perform any of a variety of functions, such as calculating physiological parameters, displaying physiological data, documenting physiological data, and/or wirelessly transmitting physiological data (including measurements or uncalculated raw sensor data) via email, text message (e.g., SMS or MMS), or some other communication medium. Moreover, any of the wireless transceivers or patient monitors described herein can be substituted with such a mobile computing device.

In the depicted embodiment, the patient monitor 216 b is connected to three different types of sensors. An optical sensor 202 b, coupled to a patient's 201 finger, is connected to the patient monitor 216 b via a cable 207. In addition, an acoustic sensor 204 b and an electrocardiograph (ECG) sensor 206 are attached to the patient monitor 206 b via the cable 205. The optical sensor 202 b can perform any of the optical sensor functions described above. Likewise, the acoustic sensor 204 b can perform any of the acoustic sensor functions described above. The ECG sensor 206 can be used to monitor electrical activity of the patient's 201 heart.

Advantageously, in the depicted embodiment, the ECG sensor 206 is a bundle sensor that includes one or more ECG leads 208 in a single package. For example, the ECG sensor 206 can include one, two, or three or more leads. One or more of the leads 208 can be an active lead or leads, while another lead 208 can be a reference lead. Other configurations are possible with additional leads within the same package or at different points on the patient's body. Using a bundle ECG sensor 206 can advantageously enable a single cable connection via the cable 205 to the cuff 212 b. Similarly, an acoustical sensor can be included in the ECG sensor 206 to advantageously reduce the overall complexity of the on-body assembly.

The cable 205 in FIG. 2B can connect two sensors to the cuff 212 b, namely the ECG sensor 206 and the acoustic sensor 204 b. Although not shown, the cable 205 can further connect an optical ear sensor to the acoustic sensor 204 b in some embodiments, optionally replacing the finger optical sensor 202 b. The cable 205 shown in FIG. 2B can have all the features described above with respect to FIG. 2A.

Although not shown, in some embodiments, any of the sensors, cuffs, wireless sensors, or patient monitors described herein can include one or more accelerometers or other motion measurement devices (such as gyroscopes). For example, in FIG. 2B, one or more of the acoustic sensor 204 b, the ECG sensor 206, the cuff 212 b, the patient monitor 216 b, and/or the optical sensor 202 b can include one or more motion measurement devices. A motion measurement device can be used by a processor (such as in the patient monitor 216 b or other device) to determine motion and/or position of a patient. For example, a motion measurement device can be used to determine whether a patient is sitting up, lying down, walking, or the like.

Movement and/or position data obtained from a motion measurement device can be used to adjust a parameter calculation algorithm to compensate for the patient's motion. For example, a parameter measurement algorithm that compensates for motion can more aggressively compensate for motion in response to high degree of measured movement. When less motion is detected, the algorithm can compensate less aggressively. Movement and/or position data can also be used as a contributing factor to adjusting parameter measurements. Blood pressure, for instance, can change during patient motion due to changes in blood flow. If the patient is detected to be moving, the patient's calculated blood pressure (or other parameter) can therefore be adjusted differently than when the patient is detected to be sitting.

A database can be assembled that includes movement and parameter data (raw or measured parameters) for one or more patients over time. The database can be analyzed by a processor to detect trends that can be used to perform parameter calculation adjustments based on motion or position. Many other variations and uses of the motion and/or position data are possible.

Although the patient monitoring systems described herein, including the systems 100A, 100B, 200A, and 200B have been described in the context of blood pressure cuffs, blood pressure need not be measured in some embodiments. For example, the cuff can be a holder for the patient monitoring devices and/or wireless transceivers and not include any blood pressure measuring functionality. Further, the patient monitoring devices and/or wireless transceivers shown need not be coupled to the patient via a cuff, but can be coupled to the patient at any other location, including not at all. For example, the devices can be coupled to the patient's belt (see FIGS. 3A and 3B), can be carried by the patient (e.g., via a shoulder strap or handle), or can be placed on the patient's bed next to the patient, among other possible locations.

Additionally, various features shown in FIGS. 2A and 2B can be changed or omitted. For instance, the wireless transceiver 216 can be attached to the cuff 212 without the use of the pocket 214. For example, the wireless transceiver can be sown, glued, buttoned or otherwise attached to the cuff using any various known attachment mechanisms. Or, the wireless transceiver 216 can be directly coupled to the patient (e.g., via an armband) and the cuff 212 can be omitted entirely. Instead of a cuff, the wireless transceiver 216 can be coupled to a non-occlusive blood pressure device. Many other configurations are possible.

FIGS. 3A and 3B illustrate further embodiments of a patient monitoring system 300A, 300B having a single cable connecting multiple sensors. FIG. 3A depicts a tethered patient monitoring system 300A, while FIG. 3B depicts a wireless patient monitoring system 300B. The patient monitoring systems 300A, 300B illustrate example embodiments where a single cable 305 can be used to connect multiple sensors, without using a blood pressure cuff.

Referring to FIG. 3A, the acoustic and ECG sensors 204 b, 206 of FIG. 2 are again shown coupled to the patient 201. As above, these sensors 204 b, 206 are coupled together via a cable 205. However, the cable 250 is coupled to a junction device 230 a instead of to a blood pressure cuff. In addition, the optical sensor 202 b is coupled to the patient 201 and to the junction device 230 a via a cable 207. The junction device 230 a can anchor the cable 205 b to the patient 201 (such as via the patient's belt) and pass through any signals received from the sensors 202 b, 204 b, 206 to a patient monitor 240 via a single cable 232.

In some embodiments, however, the junction device 230 a can include at least some front-end signal processing circuitry. In other embodiments, the junction device 230 a also includes a processor for processing physiological parameter measurements. Further, the junction device 230 a can include all the features of the patient monitor 216 b in some embodiments, such as providing a display that outputs parameters measured from data obtained by the sensors 202 b, 204 b, 206.

In the depicted embodiment, the patient monitor 240 is connected to a medical stand 250. The patient monitor 240 includes parameter measuring modules 242, one of which is connected to the junction device 230 a via the cable 232. The patient monitor 240 further includes a display 246. The display 246 is a user-rotatable display in the depicted embodiment.

Referring to FIG. 3B, the patient monitoring system 300B includes nearly identical features to the patient monitoring system 300A. However, the junction device 230 b includes wireless capability, enabling the junction device 230 b to wirelessly communicate with the patient monitor 240 and/or other devices.

FIGS. 4A and 4B illustrate embodiments of patient monitoring systems 400A, 400B that depict alternative cable connection systems 410 for connecting sensors to a patient monitor 402. Like the cable 205 described above, these cable connection systems 410 can advantageously enhance patient mobility and comfort.

Referring to FIG. 4A, the patient monitoring system 400A includes a patient monitor 402 a that measures physiological parameters based on signals obtained from sensors 412, 420 coupled to a patient. These sensors include an optical ear sensor 412 and an acoustic sensor 420 in the embodiment shown. The optical ear sensor 412 can include any of the features of the optical sensors described above. Likewise, the acoustic sensor 420 can include any of the features of the acoustic sensors described above.

The optical ear sensor 412 can be shaped to conform to the cartilaginous structures of the ear, such that the cartilaginous structures can provide additional support to the sensor 412, providing a more secure connection. This connection can be particularly beneficial for monitoring during pre-hospital and emergency use where the patient can move or be moved. In some embodiments, the optical ear sensor 412 can have any of the features described in U.S. application Ser. No. 12/658,872, filed Feb. 16, 2010, entitled “Ear Sensor,” the disclosure of which is hereby incorporated by reference in its entirety.

An instrument cable 450 connects the patient monitor 402 a to the cable connection system 410. The cable connection system 410 includes a sensor cable 440 connected to the instrument cable 250. The sensor cable 440 is bifurcated into two cable sections 416, 422, which connect to the individual sensors 412, 420 respectively. An anchor 430 a connects the sensor cable 440 and cable sections 416, 422. The anchor 430 a can include an adhesive for anchoring the cable connection system 410 to the patient, so as to reduce noise from cable movement or the like. Advantageously, the cable connection system 410 can reduce the number and size of cables connecting the patient to a patient monitor 402 a. The cable connection system 410 can also be used to connect with any of the other sensors, patient-worn monitors, or wireless devices described above.

FIG. 4B illustrates the patient monitoring system 400B, which includes many of the features of the monitoring system 400A. For example, an optical ear sensor 412 and an acoustic sensor 420 are coupled to the patient. Likewise, the cable connection system 410 is shown, including the cable sections 416, 422 coupled to an anchor 430 b. In the depicted embodiment, the cable connection system 410 communicates wirelessly with a patient monitor 402 b. For example, the anchor 430 b can include a wireless transceiver, or a separate wireless dongle or other device (not shown) can couple to the anchor 430 b. The anchor 430 b can be connected to a blood pressure cuff, wireless transceiver, junction device, or other device in some embodiments.

FIG. 5 illustrates a more detailed embodiment of a wireless transceiver 516. The wireless transceiver 516 can have all of the features of the wireless transceiver 516 described above. For example, the wireless transceiver 516 can connect to a blood pressure cuff and to one or more physiological sensors, and the transceiver 516 can transmit sensor data to a wireless receiver.

The depicted embodiment of the transceiver 516 includes a housing 530, which includes connectors 552 for sensor cables (e.g., for optical, acoustic, ECG, and/or other sensors) and a connector 560 for attachment to a blood pressure cuff or other patient-wearable device. The transceiver 516 further includes an antenna 518, which although shown as an external antenna, can be internal in some implementations.

In addition, the transceiver 516 includes a display 554 that depicts values of various parameters, such as systolic and diastolic blood pressure, SpO₂, and respiratory rate (RR). The display 554 can also display trends, alarms, and the like. The transceiver 516 can be implemented with the display 554 in embodiments where the transceiver 516 also acts as a patient monitor. The transceiver 516 further includes controls 556, which can be used to manipulate settings and functions of the transceiver 516.

FIGS. 6A through 6C illustrate embodiments of wireless patient monitoring systems 600. FIG. 6A illustrates a patient monitoring system 600A that includes a wireless transceiver 616, which can include the features of any of the transceivers 216, 216 described above. The transceiver 616 provides a wireless signal over a wireless link 612 to a patient monitor 620. The wireless signal can include physiological information obtained from one or more sensors, physiological information that has been front-end processed by the transceiver 616, or the like.

The patient monitor 620 can act as the wireless receiver 220 of FIG. 2. The patient monitor 620 can process the wireless signal received from the transceiver 616 to obtain values, waveforms, and the like for one or more physiological parameters. The patient monitor 620 can perform any of the patient monitoring functions described above with respect to FIGS. 2 through 5.

In addition, the patient monitor 620 can provide at least some of the physiological information received from the transceiver 616 to a multi-patient monitoring system (MMS) 640 over a network 630. The MMS 640 can include one or more physical computing devices, such as servers, having hardware and/or software for providing the physiological information to other devices in the network 630. For example, the MMS 640 can use standardized protocols (such as TCP/IP) or proprietary protocols to communicate the physiological information to one or more nurses' station computers (not shown) and/or clinician devices (not shown) via the network 630. In one embodiment, the MMS 640 can include some or all the features of the MMS described in U.S. Publication No. 2008/0188760, referred to above.

The network 630 can be a LAN or WAN, wireless LAN (“WLAN”), or other type of network used in any hospital, nursing home, patient care center, or other clinical location. In some implementations, the network 210 can interconnect devices from multiple hospitals or clinical locations, which can be remote from one another, through the Internet, one or more Intranets, a leased line, or the like. Thus, the MMS 640 can advantageously distribute the physiological information to a variety of devices that are geographically co-located or geographically separated.

FIG. 6B illustrates another embodiment of a patient monitoring system 600B, where the transceiver 616 transmits physiological information to a base station 624 via the wireless link 612. In this embodiment, the transceiver 616 can perform the functions of a patient monitor, such as any of the patient monitor functions described above. The transceiver 616 can provide processed sensor signals to the base station 624, which forwards the information on to the MMS 640 over the network 630.

FIG. 6C illustrates yet another embodiment of a patient monitoring system 600B, where the transceiver 616 transmits physiological information directly to the MMS 640. The MMS 640 can include wireless receiver functionality, for example. Thus, the embodiments shown in FIGS. 6A through 6C illustrate that the transceiver 616 can communicate with a variety of different types of devices.

FIG. 7 illustrates an embodiment of a physiological parameter display 700. The physiological parameter display 700 can be output by any of the systems described above. For instance, the physiological parameter display 700 can be output by any of the wireless receivers, transceivers, or patient monitors described above. Advantageously, in certain embodiments, the physiological parameter display 700 can display multiple parameters, including noninvasive blood pressure (NIBP) obtained using both oscillometric and non-oscillometric techniques.

The physiological parameter display 700 can display any of the physiological parameters described above, to name a few. In the depicted embodiment, the physiological parameter display 700 is shown displaying oxygen saturation 702, heart rate 704, and respiratory rate 706. In addition, the physiological parameter display 700 displays blood pressure 708, including systolic and diastolic blood pressure.

The display 700 further shows a plot 710 of continuous or substantially continuous blood pressure values measured over time. The plot 710 includes a trace 712 a for systolic pressure and a trace 712 b for diastolic pressure. The traces 712 a, 712 b can be generated using a variety of devices and techniques. For instance, the traces 712 a, 712 b can be generated using any of the velocity-based continuous blood pressure measurement techniques described above and described in further detail in U.S. Pat. Nos. 5,590,649 and 5,785,659, referred to above.

Periodically, oscillometric blood pressure measurements (sometimes referred to as Gold Standard NIBP) can be taken, using any of the cuffs described above. These measurements are shown by markers 714 on the plot 710. By way of illustration, the markers 714 are “X's” in the depicted embodiment, but the type of marker 714 used can be different in other implementations. In certain embodiments, oscillometric blood pressure measurements are taken at predefined intervals, resulting in the measurements shown by the markers 714.

In addition to or instead of taking these measurements at intervals, oscillometric blood pressure measurements can be triggered using ICI techniques, e.g., based at least partly on an analysis of the noninvasive blood pressure measurements indicated by the traces 712 a, 712 b. Advantageously, by showing both types of noninvasive blood pressure measurements in the plot 710, the display 700 can provide a clinician with continuous and oscillometric blood pressure information.

FIG. 8 illustrates another embodiment of a patient monitoring system 800. The features of the patient monitoring system 800 can be combined with any of the features of the systems described above. Likewise, any of the features described above can be incorporated into the patient monitoring system 800. Advantageously, in the depicted embodiment, the patient monitoring system 800 includes a cable hub 806 that enables one or many sensors to be selectively connected and disconnected to the cable hub 806.

Like the patient monitoring systems described above, the monitoring system 800 includes a cuff 810 with a patient device 816 for providing physiological information to a monitor 820 or which can receive power from a power supply (820). The cuff 810 can be a blood pressure cuff or merely a holder for the patient device 816. The patient device 816 can instead be a wireless transceiver having all the features of the wireless devices described above.

The patient device 816 is in coupled with an optical finger sensor 802 via cable 807. Further, the patient device 816 is coupled with the cable hub 806 via a cable 805 a. The cable hub 806 can be selectively connected to one or more sensors. In the depicted embodiment, example sensors shown coupled to the cable hub 806 include an ECG sensor 808 a and a brain sensor 840. The ECG sensor 808 a can be single-lead or multi-lead sensor. The brain sensor 840 can be an electroencephalography (EEG) sensor and/or an optical sensor. An example of EEG sensor that can be used as the brain sensor 840 is the SEDLine™ sensor available from Masimo® Corporation of Irvine, Calif., which can be used for depth-of-anesthesia monitoring among other uses. Optical brain sensors can perform spectrophotometric measurements using, for example, reflectance pulse oximetry. The brain sensor 840 can incorporate both an EEG/depth-of-anesthesia sensor and an optical sensor for cerebral oximetry.

The ECG sensor 808 a is coupled to an acoustic sensor 804 and one or more additional ECG leads 808 b. For illustrative purposes, four additional leads 808 b are shown, for a 5-lead ECG configuration. In other embodiments, one or two additional leads 808 b are used instead of four additional leads. In still other embodiments, up to at least 12 leads 808 b can be included. Acoustic sensors can also be disposed in the ECG sensor 808 a and/or lead(s) 808 b or on other locations of the body, such as over a patient's stomach (e.g., to detect bowel sounds, thereby verifying patient's digestive health, for example, in preparation for discharge from a hospital). Further, in other embodiments, the acoustic sensor 804 can connect directly to the cable hub 806 instead of to the ECG sensor 808 a.

As mentioned above, the cable hub 806 can enable one or many sensors to be selectively connected and disconnected to the cable hub 806. This configurability aspect of the cable hub 806 can allow different sensors to be attached or removed from a patient based on the patient's monitoring needs, without coupling new cables to the monitor 820. Instead, a single, light-weight cable 832 couples to the monitor 820 in certain embodiments, or wireless technology can be used to communicate with the monitor 820 (see, e.g., FIG. 1). A patient's monitoring needs can change as the patient is moved from one area of a care facility to another, such as from an operating room or intensive care unit to a general floor. The cable configuration shown, including the cable hub 806, can allow the patient to be disconnected from a single cable to the monitor 820 and easily moved to another room, where a new monitor can be coupled to the patient. Of course, the monitor 820 may move with the patient from room to room, but the single cable connection 832 rather than several can facilitate easier patient transport.

Further, in other embodiments, the cuff 810 and/or patient device 816 need not be included, but the cable hub 806 can instead connect directly to the monitor wirelessly or via a cable. Additionally, the cable hub 806 or the patient device 816 may include electronics for front-end processing, digitizing, or signal processing for one or more sensors. Placing front-end signal conditioning and/or analog-to-digital conversion circuitry in one or more of these devices can make it possible to send continuous waveforms wirelessly and/or allow for a small, more user-friendly wire (and hence cable 832) routing to the monitor 820.

The cable hub 806 can also be attached to the patient via an adhesive, allowing the cable hub 806 to become a wearable component. Together, the various sensors, cables, and cable hub 806 shown can be a complete body-worn patient monitoring system. The body-worn patient monitoring system can communicate with a patient monitor 820 as shown, which can be a tablet, handheld device, a hardware module, or a traditional monitor with a large display, to name a few possible devices.

Depending on the embodiment, certain acts, events, or functions of any of the methods described herein can be performed in a different sequence, can be added, merged, or left out all together (e.g., not all described acts or events are necessary for the practice of the method). Moreover, in certain embodiments, acts or events can be performed concurrently, e.g., through multi-threaded processing, interrupt processing, or multiple processors, rather than sequentially.

The various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. The described functionality can be implemented in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosure.

The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein can be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, microcontroller, or state machine. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of a method or algorithm described in connection with the embodiments disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal. In the alternative, the processor and the storage medium can reside as discrete components in a user terminal.

Conditional language used herein, such as, among others, “can,” “may,” “might,” “could,” “e.g.,” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment.

While the above detailed description has shown, described, and pointed out novel features as applied to various embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the device or process illustrated can be made without departing from the spirit of the disclosure. As will be recognized, certain embodiments of the inventions described herein can be embodied within a form that does not provide all of the features and benefits set forth herein, as some features can be used or practiced separately from others. The scope of the inventions is indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. 

What is claimed is:
 1. A wireless patient monitoring system comprising: a battery; an optical sensor configured to obtain photoplethysmographs, the optical sensor including at least one emitter configured to emit light and at least one detector configured to detect said light after attenuation by tissue of a user, said photoplethysmographs responsive to said detected light; a wireless transceiver configured to partially process said photoplethysmographs received from the optical sensor to partially determine an SpO₂ measurement; and the wireless transceiver configured to wirelessly transmit said partially processed photoplethysmographs to a second device for further processing into the SpO₂ measurement.
 2. The system of claim 1, wherein the wireless transceiver is configured to perform bandpass filtering.
 3. The system of claim 1, wherein the wireless transceiver is configured to perform signal conditioning.
 4. The system of claim 1, wherein the wireless transceiver is configured to wirelessly transmit said partially processed photoplethysmographs over Bluetooth.
 5. The system of claim 1, wherein the optical sensor is configured to be coupled to a fingertip.
 6. The system of claim 1, further comprising an adhesive for attaching the optical sensor to a user's skin.
 7. The system of claim 1, further comprising a band configured to secure the system to the user.
 8. A system comprising: a sensor assembly comprising: a battery; an optical sensor configured to obtain photoplethysmographs, the optical sensor including at least one emitter configured to emit light and at least one detector configured to detect said light after attenuation by tissue of a user, said photoplethysmographs responsive to said detected light; a wireless transceiver configured to partially process said photoplethysmographs received from the optical sensor to partially determine an SpO₂ measurement; the wireless transceiver configured to wirelessly transmit said partially processed photoplethysmographs to a second device; and the second device comprising a processor, memory, and display, the memory storing computer-executable instructions that, when executed, cause the second device to: further process said partially processed photoplethysmographs received from the sensor assembly to determine the SpO₂ measurement; display the SpO₂ measurement on the display.
 9. The system of claim 8, wherein the wireless transceiver is configured to perform bandpass filtering.
 10. The system of claim 8, wherein the wireless transceiver is configured to perform signal conditioning.
 11. The system of claim 8, wherein, when executed, the computer-executable instructions cause the second device to display a trend in SpO₂ measurements on the display.
 12. The system of claim 8, wherein, when executed, the computer-executable instructions cause the second device to assemble a database including said SpO₂ measurement.
 13. The system of claim 8, wherein, when executed, the computer-executable instructions cause the second device to wirelessly transmit said SpO₂ measurement via email or text message.
 14. A method of wirelessly monitoring physiological information, the method comprising: securing an optical sensor to a user's skin, the optical sensor including at least one emitter configured to emit light and at least one detector configured to detect said light after attenuation by tissue of a user; collecting photoplethysmographs from the optical sensor; using a wireless transceiver to partially process said photoplethysmographs received from the optical sensor to partially determine an SpO₂ measurement; and wirelessly transmitting said partially processed photoplethysmographs to a second device; and further processing said partially processed photoplethysmographs using the second device to determine the SpO₂ measurement.
 15. The method of claim 14, further comprising displaying a numerical value of said SpO₂ measurement on a display device.
 16. The method of claim 14, further comprising displaying a trend in SpO₂ measurements on a display device.
 17. The method of claim 14, wherein collecting photoplethysmographs comprises continuously collecting said photoplethysmographs over a period of time. 